BlackBerry Curve 8520 Smartphone has a features using which you can schedule an automatic On and Off of the device. This schedule can be set based on the Weekdays or Weekends.
To enable the Automatic On/Off, press the menu button and Select Options from the list of available menus.
In the Options screen, navigate to Auto On/Off menu
This would display the following Auto On/Off screen
To Specify the Automatic On and Off timing for Weekdays, first select the Enabled option and then set the timing for Turn On At and Turn Off At as shown above. Similarly you can set the auto on/off for Weekend after the Enabling the Weekend option.